textproduct: Albany

WHAT HAS CHANGED

Coastal storm will continue to impact the region through tonight with additional light snowfall, mainly for areas south and east of the Capital Region.

Winter Storm Warning for lake effect snow issued for Monday night through Tuesday night for Northern Herkimer County due to a strong single band of lake effect snow, mainly for areas north of Old Forge.

KEY MESSAGES

1. A coastal low pressure system will continue to bring some light snowfall through the late evening, many for areas south and east of the Capital Region, which will lead to slippery travel conditions.

2. Below normal temperatures are expected for much of the upcoming week along with opportunities for snowfall from both lake effect and passing clipper systems. Heavy lake effect snow accumulations are expected for portions of the western Adirondacks Monday night through Tuesday night which may result in difficult travel.

DISCUSSION

KEY MESSAGE 1...

Surface low pressure continue to organize well off the coast of the mid Atlantic States and it will be lifting northeast for tonight, passing well southeast of southeastern New England. The combination of an old frontal boundary, approaching upper level trough and strong jet streak aloft has been allowing for periods of light snow this morning. Spotter reports show a general coating to an inch or two has fallen this morning, mainly for the Capital Region on south and east. Recent radar trends and CAMs suggest this initial period of snow will become lighter and more intermittent for early this afternoon, but another round of steadier snowfall is expected for this evening into tonight as the coastal low makes its closest approach to the area. Model guidance has had a difficult time showing exactly how far west this steady round of precip will get, but recent runs seem to suggest that the Hudson Valley may be a good western edge of the precip. Some light precip may get as far north as the Capital Region and southern VT, but the highest accumulations will be across the Berkshires, Taconics and NW CT. Additional snowfall this evening will range from a coating to an inch in the Capital Region to another 1 to 3 inches for western New England and the mid Hudson Valley. This will be just enough to make things slippery once again after yesterday's and this morning's light snowfall. Winter Weather Advisory continues for southern and eastern areas through 4 AM, although the bulk of the accumulation will occur from about 5 PM through Midnight.

KEY MESSAGE 2...

A very cold air mass will be pouring into the region behind a an Arctic boundary on Monday. As the bitter cold air mass moves into the region, a strong single band of lake effect snow that develops off Lake Ontario will be impacting parts of the region for Monday night through Tuesday night. Based on the latest guidance, the bulk of this activity will be impacting northern Herkimer County within the strong westerly flow aloft, mainly for areas north of Old Forge. Have issued a Winter Storm Warning for lake effect snow, where 6 to 12 inches of snow is expected within the heaviest band for areas near Stillwater Reservoir for Monday night into Tuesday. Snowfall rates may exceed 1-2" per hour within the strongest part of the band. It should drop into Northern Herkimer County on Monday evening and hold fairly steady over far northern areas for Monday night into Tuesday, before starting to retract back closer to the lakeshore on Tuesday night. Some parts of far northwestern Hamilton County could get into the moderate snowfall as well, so an advisory could be needed there on the inland extent.

With 850 hpa temps falling to near -20 C, it will be rather cold for Monday night through Tuesday night across the entire region. Many areas will be down into the single digits on Monday night and highs will only reach the teens to low 20s on Tuesday. With breezy conditions behind the front (westerly winds gusting 20 to 30 mph), it will feel even colder and some wind chill values will be below zero at times. For now, it may stay just above Cold Advisory Criteria, but will have to be monitored. Temps may moderate ahead of the next clipper for Wednesday into Thursday, but models are already suggesting an even colder shot of frigid Arctic air for Friday into next weekend. Although it's quite a ways out, widespread below zero temps are possible, which would suggest a higher probability of needing Cold Weather headlines by that time. More lake effect will be possible during the late week and will need to watch model guidance closely for the potential for some synoptic snowfall as well, although model runs and ensemble members have been wildly different from run to run at this time, leaving this rather low confidence for now.

AVIATION /18Z SUNDAY THROUGH FRIDAY/

A variety of flying conditions start the TAF period. KGFL continues with periods of MVFR but mostly VFR conditions until tonight when light snow arrives bringing MVFR/IFR conditions. For KALB, light snow continues through 06z then patchy fog could develop through 12z then VFR conditions should return. For KPOU and KPSF, light snow continues through tonight as well with conditions ranging between IFR and MVFR through 12z. After 12z, VFR conditions should return. Light and variable winds continue through the TAF period.

Outlook...

Monday Night: Low Operational Impact. Breezy. NO SIG WX. Tuesday: Low Operational Impact. Breezy. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: Low Operational Impact. Slight Chance of SHSN. Wednesday Night: Moderate Operational Impact. Chance of SHSN. Thursday: Moderate Operational Impact. Chance of SN. Thursday Night: No Operational Impact. NO SIG WX. Friday: No Operational Impact. NO SIG WX.

ALY WATCHES/WARNINGS/ADVISORIES

CT...Winter Weather Advisory until 4 AM EST Monday for CTZ001-013. NY...Winter Weather Advisory until 4 AM EST Monday for NYZ054-060- 061-063>066. Winter Storm Warning from 7 PM Monday to 7 AM EST Wednesday for NYZ032. MA...Winter Weather Advisory until 4 AM EST Monday for MAZ001-025. VT...Winter Weather Advisory until 4 AM EST Monday for VTZ013>015.